Process for dyeing and printing shaped structures of hydrophobic organic high polymers containing ester groups



PROCESS FOR DYEING AND PRINTING SHAPED STRUCTURES OF HYDRQPHOBIC ORGANICHIGH POLYMERS CONTAINING ESTER GROUPS Paul Schlack, Leitershofen, nearAugsburg, Germany, assignor to Farbwerke Hoechst Aktiengesellschaftvormals Meister Lucius & Briining, Frankfurt am Main, Germany, acorporation of Germany .No Drawing. Filed Apr. 23, 1957, Ser. No.654,467 Claims priority, application Germany Apr. 28, 1956 8 Claims.(Cl. 8-55) The present invention relates to a process for dyeing andprinting shaped structures of hydrophobic organic high polymerscontaining ester groups.

When operating under the conditions usually applied for the dyeing ofacetate rayon or polyamide fibres the affinity to dispersion dyestuffsof the synthetic fibres, for example on the base of terephthalic acid,made of linear high-melting polyesters containing six-memberedcarbocyclic rings is in most cases not sufiicient, not even whenoperating at boiling temperature.

In order to attain a satisfactory utilization of the dyestuffsespecially when deeper shades are to be obtained, dyeing has either tobe carried out under pressure at temperatures considerably above 100 C.or dyeing auxiliaries, so-called carriers provoking a slight swelling ofthe compact fibre and thus opening it to the dyestutf molecules have tobe added.

Dyeing under pressure requires expensive apparatuses. Moreover, it hasto be taken into account that this process is not generally applicable.Thus, one will meet with difficulties when the textiles contain not onlypolyester filaments but also fibres that are very sensitive to heat.Difficulties are particularly great if the textiles contain wool, whichespecially when treated in a neutral bath, cannot be exposed totemperatures much above 100 C. This applies also to some syntheticfibres, for example, to fibres of polyvinyl alcohol. For the dyeing ofpiece-goods under pressure special devices are necessary which inpractice have not yet become popular.

Numerous substances have already been proposed for dyeing with the useof carriers, most of them, however, have more or less considerabledrawbacks such as for example too great a volatility, an offensiveodour, physiologically disadvantageous properties, a detrimentalinfluence on the fastness to light and difiiculties with regard to thelevelling of the goods, the ditficulties being especially great whendyeing mixed fabrics. This is particularly true of mixtures of fabricsconsisting of polyester material and wool.

Now I have found that shaped structures of hydrophobic organic highpolymers containing ester groups, particularly of high-melting linearpolyesters containing six-membered carbocyclic rings may be dyed andprinted with dispersion dyestuffs if compounds that are sparingly or notat all soluble in water and contain one or more lactone groups inaddition to at least one aromatic nucleus are used as auxiliaries.According to the process of the present invention there are preferablyused compounds in which the lactone ring and an aromatic nucleus arejoined by ortho-fusion (as the two rings in naphthalene). It proved tobe suitable to select such compounds as do not contain more than twoaromatic nuclei. It is furthermore of advantage to use compounds thatare somewhat, even if sparingly soluble in water. As lactones cominginto consideration for the process of the present invention, thefollowing com- Patented Aug. 30, 1960' pounds, which are all 'y-lactoneshaving S-membered lactone rings or fi-lactones having 6-membered lactonerings, may for example be mentioned:

Dilactones may also be used. By way of example there may be mentionedthe compound of the following formula:

0 w (:0 LE O...

Instead of using the above compounds separately there may of course alsobe used mixtures of the different lactones or mixtures of lactones andother usual carriers. in conjunction with suspension dyestuffs generallyused for dyeing and printing polyester goods, the lactones mentionedabove may be employed for all the usual dyeing methods such as dyeing inflocks, dyeing in the rope form, dyeing in balls, piece-dyeing in theopen vat, on the jig or on the dipping frame. The lactones mayfurthermore be applied for the pad-dyeing process and for the continuousdyeing of cables and combed material. According to a prior suggestionthese dyeing processes may be combined with a stretching process byimpregnating the unstretched cable of filaments continuously with adyestutf mixture containing, apart ingly volatile with steam, will bepreferred.

The amount of auxiliary agent to be used for the dyeing or printingaccording to the present invention depends on the etficiency i.e. on theaffinity to the fibre, which atlinity may in the case of water-solublecompounds be defined by the degree of distribution betweenbath andfibre. What amount is to be used depends moreover on the depth of shadewhich is desired, on the goods-to-liquor ratio applied and on the speedof difliusion in the fibre. It has to be taken into account in thisconnection that the pretreatment of the goods, especially thethermofixation also exerts an influence on the affinity of the swellingagents to the fibre.

When compounds are used that are not or only-to a small extent solublein water and which, as a rule, are applied together with a dispersingagent, 1-3 grams per liter .are generally sufficient. In certain casesit may even suffice to' use smaller quantities 'such ,as for example aquantity. of 0.5 gram. When operating with quantities that are a littlegreater than those mentioned.

In such cases a quantity of about 2-6 grams per litre is in generalsuflicient but there may also be used larger quantities, e.g. 8 or 10-45grams, which does, however, in general not increase the effectconsiderably. The values mentioned above apply to an averagegoods-toliquor ratio of about 1:40.

It is not absolutely necessary that the dycstuif should be present inthe bath from the beginning. The goods to be dyed may for example firstbe treated at an elevated temperature, at e.g. 80400 C. merely with thecarrier, the dyestufif being added to the bath later on, or the materialmay be pretreated in a standing bath with a solution or a dispersion ofthe carrier in order to be subsequently dyed in a second bath to which,if necessary, a comparatively small amount of a carrier is added, whichcarrier need not be the same as that used in the bath of thepre-treatment.

It is merely necessary to add a lactone of the present invention to oneof the baths as an auxiliary agent. It may be of advantage thatthecarrier used in the dyebath proper has a greater efiiciency, i.e. astronger aifiru'ty, and is added in a relatively smaller amount than thecarrier used in the pretreatment bath. The pretreatment bath may thuscontain for example a methyl phthalide or, if a lower melting point isto be obtained, a mixture of methyl phthalides whereas a lactone of thenaphthalene series is added to the dyebath.

The process of the present invention admits of dyeing in a single bathmixtures of fibres made of the polyesters coming into question and wooland other protein fibres, without any difficulties occurring with regardto the shading. In order to obtain very deep shades when dyeing suchmixtures of polyester fibres and wool, it is advisable to free the woolafter the dyeing of the synthetic fibres, first from the adheringdispersion dye stuff by way of a dithionite bath and then to dye thewool. For this cleaning operation the usual auxiliary stripping agentsmay be used such as for example surface-active quaternary ammoniumcompounds or colloids having an aflinity to dyestuffs such as polyvinylpyrrolidone or copolymers of vinyl pyrrolidone with other vinyl monomerssuch as acrylic acid.

Generally, the auxiliary agents used according to the present inventionditfer from the carrier substancesv hitherto customarily used indispersions such as, for example, halogenated aromatic compounds oresters of aromatic carboxylic acids, by their more even effect whichwill especially be noticed when there is a distinct solubility in water.In the latter case the risk of stain formation is consider-ablydiminished as the dyeing is brought about more gradually. Thus shadingis facilitated.

A manner of proceeding according to the present invention, which isespecially advantageous in the case of textile goods showing a verydense style of weaving and being diflicult to dye in a uniform manner,is to use instead of the finished lactones the hydroxyacids, on whichthe corresponding lactones are based, in form of their salts, and toclose the lactone ring during the dyeing process by acidifying the bathor by allowing it to become gradually acid and/or by means of a rise intemperature, whereupon dyestuff and lactone are absorbed by the fibre ina uniform manner, the lactone being more or less taken up in statunascendi. The present process is suitably carried out with hydroxyacidswhich are distinguished by a marked tendency to the ring closure, evenin high dilution. Consequently, this modification of the process of thepresent inven tion is especially advantageous in the case of lactonesthat are sparingly soluble in water. If necessary, also in this casedyeing is carried out in the presence of dispersing agents, especiallyin the presence of anionic or non-ionic dispersing agents. 1

In order to liberate the hydroxyacids gradually from their salts andthus to provide the conditions under which the formation of 'lactonescan take place, there may for example be applied the ammonium salts ofthe hydroxyacids. The alkali metal salts may also be used together withammonium salts. As automatic acid formers, especially in conjunctionwith alkali metal salts, there may also be added such compounds as arehydrolyzed by water into acids especially in the heat, as for exampleeasily hydrolizable esters, such as oxamic acid esters or tartaric acidesters, imides such as phthalimide, salts of halogen-carboxylic acidsthat can easily be split such as sodium chloroacetate. A gradual andcautious admixture of free acids such as formic acid, acetic acid orglycolic acid is of course also possible.

Though the proess of the present invention is preferably directed to thedyeing and printing of shaped structures made of hydrophobic organichigh polymers containing ester groups, especially of shaped structuresmade of high-melting polyesters containing six-membered carbocyclicrings as for example the polyesters of terephthalic acid, it is as ageneral principle also applicable to other hydrophobic syntheticmaterials containing a variety of ester groups in the molecule and beingdifli cult to dye such as cellulose triacetate or linear polyurethanes.As shaped structures there come for example into consideration fibres,filaments, small ribbons, hanks, foils and materials made thereof suchas textile fabrics.

The following examples illustrate the invention but they are notintended to limit it thereto.

Example 1 2.54 grams of the lactone ofZ-hydroxy-naphthalenel-fi-propionic acid are added at a temperature of60 C. to a dyebath containing in 875 cc. of water 2 grams of acondensation product from an alkyl phenol and ethylene oxide whichcondensation product was additionally esterified with sulfuric acid,0.34 gram of the dispersion dyestuif of the formula and 1 cc. of anaqueous solution of glycolic acid of 33% strength.- 17 grams of yarnmade of polyethylene glycol terephthalate (Nm 18/ 3, individual titre3.6 deniers, staple length mm.) are introduced into the liquid which hasbecome turbid by the dispersion of the lactone. The dyebath is slowlybrought to the boil. At the boiling point the bath quickly clarifies.The dyeing is carried out for one hour at 97-98 C., during which timethe bath is nearly exhausted. Subsequently the dyed material isthoroughly rinsed and washed for 20 minutes at C. in a bath containing 2grams of soap and 1 gram of sodium carbonate per litre. A full shade ofpink of a very good fastness to rubbing and washing is obtained.

Example 2 2.6 grams of 4.6-dimethyl-cumarin .dissolved in a smallquantity of methanol are admixed at 60 C. to 1 litre of a dyebathcontaining 2 grams of a condensation product from an alkyl phenol andethylene oxide which condensation product had additionally beenesterified with sulfuric acid, 0.35 gram of the dyestufi of the formulaOGHs (H) NH:

and 1 cc. of glycolic acid of 33% strength. A fine dispersion of thelactone is formed. Into the bath thus prepared there are introduced.17.3grams of a yarn of "AL-wpolyethylene glycol terephthalate (Nm 48/2, 3.0deniers, '100 mm.), which yarn had previously been fixed in the ropeform at 110 C. The bath is gradually brought to the boil while thematerial to be dyed is well moved. The dyeing process is then continuedfor one hour at 9798 C. After a boiling time of about 20 minutes, thebath, which had turned dull milky owing to the precipitatingdimethyl-cumarin, clarifies. After having been dyed the goods arethoroughly rinsed and then washed for 20 minutes at 90 C. in a bathcontaining 2 grams of soap and 1 gram of sodium carbonate per litre.

A brilliant deep bluish red shade of a very good fastness to washing andrubbing is obtained.

Example 3 4.5 grams of 6-methyl-phthalide are heated together with 15cc. of a 2 N-methanolic sodium hydroxide solution 'until the lactonering is completely opened. The solution thus obtained is then admixed at60 C. to a dyebath containing in 900 cc. of water 4 grams of ammoniumchloride, 2 grams of a condensation product from an alkyl phenol andethylene oxide which condensation product was additionally esterifiedwith sulfuric acid, and 0.36 gram of the dyestufi of the formula NH: iii CONHs H A o NH-CHa Into this dyebath are introduced 18 grams of afabric of polyethylene glycol terephthalate (3 deniers) and the bath isthen slowly heated to the boiling point. After 20 minutes the pH valueof the bath is adjusted to 6 by cautious addition of mineral acid. Thedyeing is completed within 70 minutes at a temperature of 9798 C., thegoods to be dyed being constantly moved during this time. Finally thefabric is thoroughly rinsed and then washed for 20 minutes at 90 C. in abath containing 2 grams of soap and 1 gram of sodium carbonate perlitre.

A clear deep blue shade of a very good fastness to washing and rubbingis otbained.

Example 4 4.5 grams of 4.6-dimethyl-cumarin are heated together with 15cc. of a 2 N-methanolic sodium hydroxide solution until the lactone ringis completely opened. The solution of the sodium dimethyl-cumarate isthen admixed at 60 C. to a bath containing in 900 cc. of water 4 gramsof ammonium chloride, 2 grams of a condensation product from an alkylphenol and ethylene oxide which condensation product was additionallyesterified with sulfuric acid, and 0.36 gram of the dyestuff mentionedin Example 3. After having introduced 18 grams of a fabric ofpolyethylene glycol terephthalate into the bath the latter is slowlyheated to boiling and boiled for 20 minutes. By the addition of mineralacid the pH value of the bath is then adjusted to 5-6. Further dyeingand working up are carried out as described in Example 3. In this case,too, a clear deep blue shade of a very good fastness to Washing andrubbing is obtained.

Example 5 onto GEN-ON: Q

and naphthalene sulfonic acid, and 1 cc. of glycolic acid of 33%strength. The bath remains clear. Into the dyebath thus prepared thereare introduced 21.25 grams of a yarn made of polyethylene glycolterephthalate (Nm 48/2, 3 deniers, mm., fixed prior to dyeing with steamat C.). The dyebath is slowly brought to the boil. The material is dyedfor 1 hour at 97-98 C. while it is constantly moved. The bath is almostcompletely exhausted thereby. After having been rinsed thoroughly thegoods are soaped for 20 minutes as described in Examples 1-3. The dyeingobtained is fast to washing and rubbing.

Example 6 2.8 grams of the lactone of Z-hydroxynaphthalene-l-B-propionic acid dissolved in a small quantity of methanol are added whilestirring to 1 litre of a bath containing 2 grams of a condensationproduct from an alkyl phenol and ethylene oxide which condensationproduct was additionally esterified with sulfuric acid, 1 cc. ofglycolic acid of 33% strength and 0.425 gram of the dispersion dyestuffof the formula I l 02 i NH} Into the dull milky bath thus obtained thereare then introduced 21.25 grams of a yarn made of polyethylene glycolterephthalate (Nm 48/2, 3.0 deniers, 100 mm., fixed in the dry state atC.) and the bath is slowly heatedto boiling. After a boiling time of lhour which suflices to practically exhaust the bath, the goods. arethoroughly rinsed and then washed at 90 C. as described in Examples 1-3.

The dyeing obtained has a good fastness to washing and rubbing.

Example 7 A concentrated solution of sodium dimethyl cumaratecorresponding to 2.7 grams of 4.6-dimethyl-cumarin and 0.4 gram ofdimethyl oxalate are added at 50 C. to a bath containing in 900 cc. ofwater 0.36 grain of the dyestutf of the formula ll 0 NH;

which dyestuff was dispersed in a mixture of 0.036 gram ofdibutyl-naphthalene-sulfonic acid and 0.36 gram of a dispersing agentthat had been obtained by condensation of cresol, formaldehyde andsodium sulfite and by subsequently heating the product obtained withfl-naphthalene sulfonic acid, formaldehyde and sodium sulfite.

After having introduced into the bath 18 grams of a fabric as has beendescribed in Example 4 the bath is gradually heated to the boil andboiled for 10 minutes. Its pH value is then adjusted to 4.5 by means ofacetic acid. The fabric is boiled for another 50 minutes and thencompleted in the way described in Example 3.

A very clear deep and reddish violet dyeing is obtained.

During the whole of the dyeing process the bath remains clear. There isno disadvantageous formation of foam. In order to increase the securityof working there may be added a small quantity of a condensation productfrom naphthalene sulfonic acidand formaldehyde. Practically the samedepth of shade is obtained when the sodium dimethyl cumarate is replacedby the sodium salt of cumaric acid of 4-methyl-cumarin.

7 Example 8 2.1 grams of the dilactone of the formula (IZHs I OH and 6.9grams of phthalimide serving as acid forming agent. After havingintroduced 14 grams of a fabric of polyethylene terephthalate into thebath the latter is slowly heated to the boil, whereby the previouslysuspended phthalimide dissolves. After 1 hours dyeing at boilingtemperature the goods are thoroughly rinsed. A clear yellow dyein ofmedium depth and of good fastness to wet processing is obtained.

Example 9 A solution of sodium cumarate obtained by heating 2.2 grams ofcumarin together with 0.65 grain of sodium hydroxide in a small quantityof methanol, is admixed at 45 C. to a dyebath containing in 750 cc. ofwater 0.3 gram of 1,4,5,S-tetra-arnino-anthraquinone and 1.5 grams ofN-dimethyl-N-fl-hydroxyethyl-N-stearoylamidopropylamrnonium-hydrogenphosphate and 1.45 grams of dimethyl oxalate.After addition of 14.9 grams of a poplin fabric of polyethyleneterephthalate the bath is brought to the boil. After 1 hours boiling thegoods are rinsed and soaped again at 70 C. A clear deep dyeing of a goodfastness to wet processing is obtained.

I claim:

1. A process for dyeing and printing shaped structures 35 of hydrophobiclinear organic high polymers containing ester groups with dispersiondyestuffs which comprises dyeing said structures in the presence of anaromatic compound containing from one to two aromatic rings andsubstituted by from one to two lactone rings having from 5 to 6 ringmembers.

2. A process for dyeing and printing textile materials of hydrophobiclinear high melting organic polyesters containing six-memberedcarbocyclic rings with dispersion dyestuffs which comprises dyeing saidmaterials in a bath in the presence of an aromatic compound containingfrom one to two aromatic rings and substituted by from one to twolactone rings having from 5 to 6 ring mem: bers.

3. The process defined in claim 2 wherein the aromatic compound is abenzene having a lactone ring with from 5 to 6 ring members joinedthereto by ortho-fusion.

4. The process as defined in claim 2 wherein the textile material is,before dyeing, contacted in an aqueous bath with an aromatic compoundcontaining from one to two aromatic rings and substituted by from one totwo lactone rings having from 5 to 6 ring members.

5. The process as defined in claim 2, wherein said lactone substitutedaromatic compound is formed during dyeing, by acidification of saidbath, from a salt of that hydroxy-carboxylic acid corresponding withsaid lactone.

6. The process as in claim 2, wherein said lactone substituted aromaticcompound is formed during dyeing, by acidification of said bath, fromthat hydroxy-carboxyh'c acid corresponding with said lactone.

7. A process as claimed in claim 2 wherein said aromatic compound is4,6-dimethyl cumarin.

8. A process as claimed in claim 2 wherein said aromatic compound is thelactonc of Z-hydroxynaphthalenc- I-B-propionic acid.

OTHER REFERENCES Am. Dyestuif Reporter, Nov. 13, 1950, p. 790. TheTechnical Bulletin of Du Pont, vol. 8, No. 2, June 1952, pp. 69-78.

1. A PROCESS FOR DYEING AND PRINTING SHAPED STRUCTURES OF HYDROPHOBICLINEAR ORGANIC HIGH POLYMERS CONTAINING ESTER GROUPS WITH DISPERSIONDYESTUFFS WHICH COMPRISES DYEING SAID STRUCTURES IN THE PRESENCE OF ANAROMATIC COMPOUND CONTAINING FROM ONE TO TWO AROMATIC RINGS ANDSUBSTITUTED BY FROM ONE TO TWO LACTONE RINGS HAVING FROM 5 TO 6 RINGMEMBERS.